PROJECT SUMMARY Glaucoma is a leading cause of irreversible blindness and disability. The disease can remain relatively asymptomatic until the late stages; therefore, early detection and monitoring of vision damage is paramount to prevent functional impairment and blindness. Detection of functional visual loss in the disease has traditionally been made using standard automated perimetry (SAP). However, SAP testing is limited by the cost and complexity of its procedure, the subjectivity of patient responses, the large variability among subsequent tests, and the lack of portability of the equipment. The overall goal of this proposal is to address the limitation of currently available techniques by developing a portable objective method for the assessment of visual field loss in glaucoma. The founders of NGoggle Inc. have demonstrated that the use of multi- focal steady-state visual evoked potentials (mfSSVEPs) provides a simpler, more consistent and objective way to assess visual system integrity. Compared to the existing technologies, mfSSVEP-based perimetry will be simpler to perform, faster in producing the results and perhaps more accurate in the diagnosis due to better signal-to-noise ratios (SNRs) of its acquired data. In this Phase I SBIR project, we will leverage the founder?s discoveries and innovations to develop the NeuroGoggle, a portable objective method for assessing human functional visual field loss. The NeuroGoggle assesses patient?s visual function based on his/her mfSSVEP responses that is evoked by a constellation of multi-frequency multi-focal visual stimuli presented by a head-mounted display and recorded using a wireless EEG acquisition system. This project has the Specific Aim: To develop a wearable objective high-precision mfSSVEP-based visual field assessment prototype system, which will be comfortable to wear, easy to operate and capable of acquiring high-SNR EEG/EOG signals robustly in real-world environments. Successful development of the NeuroGoggle will provide a much-needed device that will enable patients to administer visual function tests quickly and easily at home by themselves or with the help of a companion. This will hence reduce the required number of office visits and lighten the economic and emotional burden of the disease.